PYQT5 Getting text from the Window title?

Question

I hope I have a simple question. I have a pyqt mainwindow that has an mdi area for sub-windows. I would like to be able to get the text of the title from a current sub-window and set it to a variable.

The reason I am doing this is that when you click on other sections of my main window I have mdi sub-windows that open up to edit the data that has been entered. I would like the user to be able to open and edit multiple sets of data at once and I am setting the directory key for the data in the title bar. I thought it would be a good way to differentiate between which set of data is being edited at the current moment.

I'm not sure if this is the best way or even a good way to achieve what I would like. If there is another method that would be better I would love to hear it.

Thank you for all your time.

Answer 1

The QMdiArea provides a method QMdiArea::activeSubWindow() as well as a signal QMdiArea::subWindowActivated().

The QMdiSubWindow is (directly) derived from QWidget which in turn provides a property QWidget::windowTitle.

Putting this altogether, it should work.

I prepared an MCVE as "proof of concept" (and to train my Python/PyQt skills).

Sample code testQMDIActiveSubWindow.py:

#!/usr/bin/python3

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QMdiArea, QMdiSubWindow

def updateActiveChild(subWindow):
  win.setWindowTitle("MDI Test: '%s'" % subWindow.windowTitle())

if __name__ == '__main__':
  app = QApplication(sys.argv)
  # build GUI
  win = QMainWindow()
  win.resize(640, 480)
  mdiArea = QMdiArea()
  for title in ["Data:1", "Data:2", "Data:3", "Data:n"]:
    mdiChild = QMdiSubWindow()
    mdiChild.setWindowTitle(title)
    mdiArea.addSubWindow(mdiChild)
  mdiArea.tileSubWindows()
  win.setCentralWidget(mdiArea)
  win.show()
  updateActiveChild(mdiArea.activeSubWindow())
  # install signal handlers
  mdiArea.subWindowActivated.connect(updateActiveChild)
  # exec. application
  sys.exit(app.exec_())

I tested it in python3, cygwin64, Windows 10 (64 bit):

The title of active sub-window is reflected in the title of the main window.